Conventionally, a manual feeding unit has been employed in printing on non-standard sheet, OHP, thick paper, or the like with a copying machine. The manual feeding unit comprises a tray placing a sheet and a member for guiding edges arranging parallel to the sheet-feeding direction. The most of the manual feeding units has a structure for determining the size of the placed sheet in the main scanning direction by sliding the guiding member in the main scanning direction.
On the other hand, the size in the sheet-feeding direction (the sub scanning direction) is assumingly determined as the maximum size presumable from the sheet size in the main scanning direction. When the actual size of the sheet in the sheet-feeding direction is smaller than the assumed maximum size, the rear end edge of the sheet is detected by a sensor and the printing is forcedly stopped in detecting the rear end edge in accordance with the installed program. If the printing is stopped, however, the document scanning operation continues till the maximum size of the document is scanned completely. The carriage thus continues the unnecessary operation even after the printing is stopped.
In addition, the size in the sheet-feeding direction is an assumed size, and thus the scanner performs the scanning assuming the sheet has the presumable maximum size in the sheet-feeding direction. Therefore, when the actual size in the sheet-feeding direction is smaller than the assumed maximum size, the redundant data in an area in which the actual document is not exist is rejected. This process terribly decreases the scanning operation speed in printing with use of the manual feeding unit. In other words, the printing speed with use of the manual feeding unit cannot be increased due to this process.
Further, according to the conventional apparatus the printing has to be started in the condition where the size in the sheet-feeding direction is assumingly determined as the presumable maximum size. The sorts of functions that can be used in this condition are so limited in comparing with the printing using a sheet-feeding cassette. More specifically, in order to set the binding space, the area to be printed needs to be adjusted. The adjustment is useful in the case where the document size is given. When the printing is performed with use of the manual feeding unit, however, the precise sheet size in the sheet-feeding direction is not given. In such a condition, the area to be printed cannot be adjusted, and thus the adjusting operation will be determined as invalid.
Further, the conventional manual feeding unit detects the size of the sheet in the main scanning direction. The apparatus thus needs to be provided with a size detecting mechanism and a sensor, and the components increases, which complicates the structure of the apparatus, resulting in the increase of the manufacturing cost.
FIG. 1 shows the structure of the digital copying machine as the conventional image apparatus to describe in detail.
As shown in FIG. 1, the copying machine comprises as a basic structure a main controlling section 201, a scanner controlling section 203, an automatic document feeding section 205, a printer engine controlling section 204, a sheet feeding controlling section 206, an automatic document upsetting section controlling circuit 209, and a sheet feeding cassette 207.
The copying machine further comprises a manual feeding tray 208 having a sheet size detection circuit 217 for detecting the sheet size in the main scanning direction. An automatic document upsetting section 216 does not detect the sheet size, and thus has no sensor. Similarly, a sheet guide controlling section 210 also does not perform the sheet size detection, and thus controls a motor merely to align the stacked sheets.
As shown in the diagram, the conventional copying machine has a rear end edge detection circuit 218 for detecting the sheet feeding direction in feeding the sheet. After detecting the rear end edge of the sheet by this section, the printer engine controlling section 204 performs a processing of stopping the printing by force.
On the other hand, with the conventional copying machine, the user can manually set the sheet size in the manual feeding printing.
The operation of the digital copying machine as the conventional image forming apparatus will be described in detail with reference to the flow chart of FIG. 2.
The user sets a document on a document mounting table (step S101), aligns sheets on the manual feeding tray 208 (step S102), sets the size of the sheet manually fed by operating a control panel 202 (step S103), and pushes a start button on the control panel 202 (step S104).
After pushing the start button, the parameters are set in accordance with the sheet size (step S105), and then the first sheet is picked up from the manual feeding tray 208 to be fed into the inside of the apparatus (step S106) to be subjected to the predetermined printing process (step S107), ejected thereafter (step S108).
When the manual feeding tray 208 mounts more than one sheet, the sheets are serially picked up from the manual feeding tray 208 to be subjected to the printing process (steps S109 to 111).
If the sheet size is wrongly set in the above-mentioned process, the document size and the sheet size does not match each other, which prevents the proper printing. With the result, unclear printing may occur and the printing efficiency will be adversely affected.
The present invention has been developed in consideration of the above, and is intended to automatically determining the sheet size in the sheet conveying direction prior to the printing operation such that various settings or processings can be attained prior to the printing. Further, the redundant scanning operation exceeding the sheet size does not need to be performed since the sheet size can be specified prior to the printing operation. As a result, the interval between the printing operations can be decreased, and thus the printing speed can be increased. In addition, according to the present invention, the sheet size is automatically preformed and user does not need to perform the complicated operation, and thus the printing efficiency is remarkably improved. Still further, according to the present invention, the manual feeding unit may have only a sheet holding function, and can be formed in a simple structure, resulting in the decrease of the manufacturing cost.
In order to attain the above-mentioned object, the present invention provides an image forming apparatus for reading an image on a document having a main scanning direction and a sub scanning direction and forming a copy image of the image on a copy image forming medium, comprising: a conveying section which automatically conveys the document; a reading section which reads the image on the document; an image forming section which forms an image on the copy image forming medium; a sheet feeding section having a plurality of sheet feeding cassettes respectively containing corresponding one of sizes of the copy image forming mediums, and a manual feeding tray for manually stacking a desired size of the copy image forming mediums, the sheet feeding section feeds sheets selectively from one of the manual feeding tray and the sheet feeding cassettes; an automatic document upsetting section which two-dimensionally detects a size of a first one of the copy image forming mediums fed from the manual feeding tray when the sheet feeding section selects the manual feeding tray to feed the copy image forming mediums therefrom; and a controlling section which controls the reading section to read the image in accordance with the detected size of the copy image forming mediums, and controls the image forming section for forming the copy image on the copy image forming mediums.
The present invention further provides an image forming apparatus for reading an image on a document having a main scanning direction and a sub scanning direction and forming a copy image of the image on a copy image forming medium, comprising: a document conveying section which automatically conveys the the document; a reading section which reads the image on the document; an image forming section which forms an image on the copy image forming medium; a sheet feeding section having a plurality of sheet feeding cassettes respectively containing corresponding one of sizes of the copy image forming mediums, and a manual feeding tray which manually stacks a desired size of the copy image forming mediums, the sheet feeding section feeds sheets selectively from one of the manual feeding tray and the sheet feeding cassettes; an automatic document upsetting section having a copy image forming medium aligning guide movable in two directions and an optical sensor for optically detecting one of a presence and an absence of the copy image forming medium, the automatic document upsetting section which two-dimensionally detects a size of a first one of the copy image forming mediums fed from the manual feeding tray in accordance with a moving distance of the copy image forming medium aligning guide and an output signal of the sensor; and a controlling section which controls the reading section to read the image in accordance with the detected size of the copy image forming mediums, and controls the image forming section for forming the copy image on the copy image forming mediums, and, when the image forming section forms the copy image on a plurality of the copy image forming mediums, the controlling section controls the image forming section to form a first image by feeding one of the copy image forming mediums from the automatic document upsetting section, and controls the image forming section to form a second image by feeding one of the copy image forming mediums from the manual feeding tray.
Still further, the present invention provides an image forming apparatus for reading an image on a document having a main scanning direction and a sub scanning direction and forming a copy image of the image on a copy image forming medium, comprising: a document conveying section which automatically conveys the document; a reading section which reads the image on the document; an image forming section which forms an image on the copy image forming medium; a sheet feeding section having a plurality of sheet feeding cassettes respectively containing corresponding one of sizes of the copy image forming mediums, and a manual feeding tray for manually stacking a desired size of the copy image forming mediums, the sheet feeding section feeds sheets selectively from one of the manual feeding tray and the sheet feeding cassettes; an automatic document upsetting section having a mechanical sensor for mechanically detecting one of a presence and an absence of the copy image forming medium, the automatic document upsetting section two-dimensionally detects a size of a first one of the copy image forming mediums fed from the manual feeding tray in accordance with an output signal of the sensor; and a controlling section which controls the reading section to read the image in accordance with the detected size of the copy image forming mediums, and controls the image forming section for forming the copy image on the copy image forming mediums, and, when the image forming section forms the copy image on a plurality of the copy image forming mediums, the controlling section controls the image forming section to form a first image by feeding one of the copy image forming mediums from the automatic document upsetting section, and controls the image forming section to form a second image by feeding one of the copy image forming mediums from the manual feeding tray.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.